Metoprolol in acute myocardial infarction. Other clinical findings and tolerability. The MIAMI Trial Research Group.

Fifteen minutes after injection there was a fall in mean heart rate (18%, p less than 0.001), systolic blood pressure (10%, p less than 0.001) and rate-pressure product (27%, p less than 0.0001) in the metoprolol group of patients in the MIAMI trial. Hypotension and bradycardia not necessarily associated with withdrawal of drug were more common in the metoprolol group (p less than 0.001). Atrioventricular block I was more common in the metoprolol group (p less than 0.03), whereas no such difference was observed for atrioventricular block II and III, asystole or pacemaker implantations. Left ventricular failure was observed no more often in the metoprolol group. The occurrence of cardiogenic shock also did not differ between the groups. Cardiac glycosides were used more in the placebo group, but diuretic and furosemide usage did not differ. For all patients mean furosemide doses and number of diuretic injections were similar in both treatment groups. Atropine (4.1 vs 6.4%) and sympathomimetic (3.2 vs 4.6%) agents were used more often in the metoprolol group during days 0 to 5 (p less than 0.05). The trial medication was withdrawn temporarily more often in the metoprolol than in the placebo group (p less than 0.001). However, permanent withdrawal of trial medication occurred with a similar frequency overall in both groups. More patients were withdrawn from the study because of cardiovascular reasons in the metoprolol group (9%) than in the placebo group (5%, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)